316 TROPICAL NATURE, AND OTHER ESSAYS. 



bears, are also very cliaracteristic, though by no means 

 confined to the region. 



Among birds the most important group is certainly 

 the small-sized, but highly-organized warblers (Sylviidse), 

 which, although almost universally distributed, are more 

 numerous, and have more peculiar and characteristic 

 genera here than in any other region. Most of our 

 song-birds, and many of the commonest tenants of our 

 fields, woods, and gardens, belong to this family; and 

 identical or representative species are often found rang- 

 ing from Spain to China, and from Ireland to Japan. 

 The reedlings (Panuridse), the tits (Paridse), and the 

 magpies (Pica), are also very characteristic ; while 

 among the finches (Fringillidse), a considerable number 

 of genera are peculiar. A large number of peculiar 

 groups of grouse (Tetraonidse), and pheasants (Pha- 

 sianidse) are also characteristic of this region. Although 

 the reptiles and fresh-water fishes are comparatively 

 few, yet many of them are peculiar. Thus, no less than 

 2 genera of snakes, 7 of lizards, and 16 of batrachia, 

 are confined to the Palsearctic region, as well as 20 

 genera of fresh-water fishes. 



The insects and land-shells ofi'er their full proportion 

 of peculiar types; but it would lead us beyond our 

 special object to enter into details with regard to these 

 less known groups of animals.^ 



1 Details will be found in the Author's work on The Geographical Dis- 

 tribution of Aniraals. 



